The Diabetes Prevention Protocol (DPT-1), begun 2 years ago, is proceeding as scheduled according to the original protocol. The objectives of both the parenteral antigen protocol and the oral antigen protocol are specifically to determine whether intervention with parenteral or oral insulin in prediabetes will delay or prevent the development of clinical IDDM in 'high risk' (parenteral antigen) or 'intermediate risk' (oral antigen protocol) nondiabetic relatives of patients with IDDM. Currently, nationally, the parenteral antigen protocol has been activated and the oral antigen protocol is to be activated in September, 1996, with 131 subjects nationally eligible for enrollment. Please note that, at Duke, we are conducting screening tests but not intervention protcols. Within the past twelve months, we have screened 15 subjects, 7 male, 8 female, and all Caucasian for islet cell antibodies. One of these subjects showed positive islet cell antibodies. We have appreciated the services of the General Clinical Research Center in conducting intravenous glucose tolerance tests on three islet cell antibody subjects, all male and all white. All three subjects had normal intravenous glucose tolerance tests, but one had positive insulin antibodies and will be eligible for the oral antigen protocol. No patients have had adverse sequellae of testing. We recognize that the small sample studied at Duke is not diverse by race or gender, but we do not actively recruit for this study, and will do so only at the suggestion of the national steering committee. Nationally, the goal is to screen a total of 60,000 relatives, and the majority of those subjects have already been studied, ahead of schedule. At this time, a national effort is being made of more timely follow up of "at risk" study subjects. We anticipate continuing this study for one to two more years. Currently, we are not considering expanding to the parenteral and oral antigen intervention protocols.